Lubricating oil composition



United States Patent" 2,725,359 LUBRICATING om COMBOSITION Denham Harman, Ori'n'da, and Ru ert C'. Morris, Forrest J. Watson, and Hyman Diamond; Berkeley, Calif., assignors to Shell Development Company, Emery ville, Califi, a corporation of Dclaware No-Drawing. Application March 7, 1. 951,: SerialNo.-214,432.

13 claims; ((51: 252M928) This invention relates to i'riiprov'ed lubricating com.- pcsitions and a class of organic compounds particularly adapted to improvethe'properties'of li'quids and/or solids which are suitable for use as fluid' lubricants, greases, coolants, rustand/or corrosion-inhibiting compositions, coating compositions, and the like. More particularly, this invention pertains to lubricants such as natural or synthetic" lubricants; emulsions; aqueous solutions, and organic and/or inorganic materials which can'be adapted for" lubricating purposes, which lubricants possess improved chaarcteristics due to the addition thereto of a class of multifunctional organic compounds capable of stabilizing, and impartingextreme pressure, anti-wean. and anti-fouling properties to lubricating compositions, as Well as acting as an inhibitor of oxidation and corrosion.

It is well known tha'tv'ario'us lubricants; wh'e'ther doped o'ru nd'oped tend to oxidize and to formcorrosive bodies and sludge when: used-T in modern en ines and machines operating under" ordinary conditions or at high speeds, low or elevated temperatures, under'heavy loads audiolother a'dyerseeondi'nicsn's. some of" the deterioration products of lubricants formed during their" use are hard carbonaceous materials which adhere to metal surfaces wliiclf results in a gradual or ra'pid'wearing away of metal parts. The damage thus caused requires replacement of such parts or even the complete overhauling of engines and machines, resulting. in expensive loss of production and time. p

In the case of the highest quality non-corrosive stable lubricating" oils, which have been highly refined for specific uses, or synthetic lubricants developed for specific or special uses, it has been observed that such: oils or lubricants are generally highly susceptible 't'o oXidation and" deterioration becoming progressively more corrosive inengines and machines even under ordinary operating conditions.

To improve the? lubricating propcrties of oils and syntheticlubricants it has become the practice to blend with various lubricants at? leastone addition agent, which additive has the effect orproperty of inhibiting deterioration of lubricants and imparting: 'to' than certain beneficial properties: Thus, additives'nha e been specifically designedwhich have theproperty' of inhibiting the corrosion ofalloyed bearings, such as copper-lead, cadmium-silver, and like bearings developed for automotive, diesel, and aircraft engines} dueto acidic oxidation or decomposition components formed in lubricants during use. The additive inhibits or prevents such attack by the formation of a pi oteetivo fil-rn on the bearing surface. Additives have also been developed which possess the property of modifying the carbonaceous materials formed by deterioration oflubricantson piston rods; rings, valves, and other metal parts in internal combustion engines, automotive and truck engines, aviation engines, high-speed ice diesel engines and the like. Suchadditives serve a very important function because, by' modifying" this carbonaceous material so thatit can: be removed easily; the tendency of engine parts to become stuck is decreased so that the ring'sticking, piston scufiing, scratching, and wearing away of engine parts are, prevented or materially inhibited.

Other additives have been developed for the purpose of acting as detergents in lubricants in: order to assist in the p'epti'za'tion-ofi soot,-sludge, varnish, or lacquer formed from deteriorationof the oil when subjected to high operating. temperatures. Detergents, due to their cleaning anddispersing actiomprevent the deposition-of these deleterious materials and? assist in their removal} Amtwear additives have the property: of reducing the' wear of movable metalparts;

The use of a pluralityyof additives" in a single lubricant has beendueto: the" fact that most such additives are capable of functioning. in substantially onlyone specific manner. Thus; a: good antioxidant: may notbe able to inhibit lacquer and varnish formation on'piston rodsor to' act as a detergent or corrosion inhibitor; Inmany casess'it is found that arr additive" possesses very good properties in one respect,. but is. detrimental asan addi= tive i11 another respect. Therefore a-second additive may be. required. to counteract a detrimental effect-o1"; another Wise desirable additive. The combination of addit e's' lubricants wherein: each additive exerts its desired i-ii' fluence withoutadversely interfering. with the functions of other additives isa: diiii'cult goal to attain.

Additives which are used in lubricants for industrial purposes such as in cutting; drawing, quenching; and rolling operations: must impart to said lubricants fil'n'i strength, corrosion-inhibiting, and detergent pro erties; as Well as aid the base lubricant to cool and lubricate the base metal or other surfaces under the most adverse c0nditions of lubrication and the like.

It is a principal object of this invention to provide improved lubricating compositions comprising various fluid lubricating media and a mtlltifunc'tional additive material.

7 Another object of this invention is to add to. compounded or d'ope'd lubricants amultifunctional material whereby a synergistic effect is produced, resulting in a producfofi acc'entuatedand improved properties. Another object of this invent-ion is to add to ol'eaginous materials, organic and inorganicliquid lubricants, including" mineral lubri catiri'g oils,- synthetic lubricants of various types, and the like, a multifunctionalmaterial so as to inhibit oxidation, at both low andhigh temperatures, and corrosion and also prevent the formation: of sludge, varnish, and lacquer in said lubricantsevenunder adverse operatingv conditions. Still another object of this invention is to use in ll'lbrh eanng compo'sitionsamultifunctional material which prevents ringst'icking, as well as the sticking of other'en gine parts, due' to deterioration of the lubricant. Also, it' is an object of this invention to use in oleaginous materials, e-'.- g., in lubricating compositions, a multifunctional material which inhibits wear, scuffin'g, scratching, and other damage-normally caused to engine parts. Also, it is an object of this invention to improve the lubricating and cooling properties of base materials adapted for use in cutting, quenching, drawing; and rolling operations by addition to" said base materials a multifunctional material of this invention. Furthermore, it is an object of this in venticn to" rovide novel multifunctional lubricating agents,- which may be used as lubricants, per se, as well as for improving and enhancing the properties of lubrieating base stocks. Other objects of this invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends thisinvention consists of features which willbe here inafter fully described and particularly pointed out in the wherein each A can be independently selected from the same or different hydrocarbyl radicals or polar-substituted hydrocarbyl radicals, preferably having at least three (3) carbon atoms, wherein the polar-group can be amino, nitro, cyano, sulfo, keto, carboxyl, hydroxyl, thiol,

tion and furthermore constitute a new class of compounds etc., and wherein the PA group contains the PC linkage; X can be the same or different divalent radicals O, S, -Se--, Te, and NA"'' and preferably are selected from the group having elements of the chalkogen family of which those with atomic numbers of 8 and 16, namely, oxygen and sulfur are preferred; A can be the same or different, but preferably the same, polar substituted or unsubstituted divalent hydrocarbyl radicals (hydrocarbylene or hydrocarbylidene), the polar group being selected from those which may be present in A, A" can be the same as A and preferably is an alkylene, arylene, or cycloalkylene radical, A' can be hydrogen or the same as A, n is zero or 1, m can be zero or an integer varying from 1 to about 20, and x is an integer of 1 or 2. By a hydrocarbyl radical is meant a radical obtained by removing one or more hydrogen atoms from the same or different carbon atoms of a hydrocarbon.

A preferred class of compounds for use in the practice of the invention, and coming Within the broader class de fined before, is the class which is representable by the general formula \T /PR 0 w 2 II wherein each R is selected independently from functionally saturated organic radicals, preferably functionally saturated hydrocarbyl radicals, i. e., radicals devoid of olefinic or acetylenic unsaturation, but including aromatic radicals; Ris a divalent organic radical containing essentially a hydrocarbon or oxahydrocarbon radical connecting the phosphorus atom (P) and the oxygen atom (O) by an unbroken chain of carbon atoms or an unbroken chain of oxygen and .carbon atoms, R being joined directly to P by a PC linkage, wherein the C atom thereof is joined by three separate single valences to three different atoms or groups of atoms, and R is joined to the oxygen atom (O) by a C--O linkage. Except for the foregoing limitations, R can be a corresponding substituted hydrocarbon or substituted oxahydrocarbon radical consisting essentially of hydrocarbon or oxahydrocarbon bearing minor proportions of substituents such as halogen, oxy, hydroxy, amino, hydrocarbyloxy, nitro, sulfonate, and the like atoms or 'groups. The term oxahydrocarbon is meant to include polyoxahydrocarbons and is illustrated by such divalent radicals as methyleneoxymethylene (2- oxapropylene-1,3), ethyleneoxyethylene (3 oxapentylene- 1,5); ethyleneoxyethyleneoxyethylene (3,6-dioxaoctylene- 1,8); (polyethyleneoxy) ethylene; propyleneoxy propylene 2,5-dimethyl-3oxapentylene- 1,5 trimethylene-oxytrimethylene (4-oxaheptylene-l,7). The R' radicals preferably should have a carbon content of from one to about having'valuable properties as noted hereinafter.

Some illustrative compounds which are representative of the class defined by Formula II and which are suitable for use in the practice of the invention are:

Bis (diamyl phosphono methyl] ether, Bis (dilauryl phosphono) ethyl] ether, Bis (dibutyl-S-phosphono) 3-oxapentyl] ether, Bisf(dipropyld phosphono)1,4' dimethyl-3-oxapentyllether, Bis (dihexyl-8-phosphono) 3,6-dioxaoctyl 1 ether, Bis I (butyl benzenephosphinico)ethyl] ether, Bis I-2(butyl p-chlorobenzenephosphinico)ethyl]ether, Bis diamyl 3-phosphono)2-oxa-propyl] ether, Bis dibutyl 3-phosphono) Z-hydroxy-propyl] ether.

The polyphospho organic compounds of this invention can be prepared in a number of ways. For example, a bis(dihydrocarbyl phosphonohydrocarbyl) ether, which an be represented by the general formula (R0) 0 0 OR R O R i (RO)/ OR III can be prepared by reacting a trihydrocaroyl phosphite with bis(halohydrocarbyl) ether; bis(dihydrocarbyl phosphonooxomethyl) ether. The reaction is representable as follows:

wherein the Rs are hydrocarbyl radicals.

Another method of preparing compounds of the class as represented by Formula V is by reacting polyalkylene glycol with phosgene to form the bis(chloroformyloxy poly-alkyleneoxy) alkylene and thereafter treating the resultant product with an organic phosphite. The reaction proceeds as follows:

O 0 mohfJc on-o)...R-o-ii-i*(on), ZRCI wherein the Rs are the same as in Formula III and m is the same as in Formula I.

To illustrate the present invention further, the following examples are presented, with the understanding, however, that various modifications can be resorted to Without departing from the spirit and scope of the invention. The thioether and amino derivatives of compounds under discussion can be prepared by hydrobromination of diallyl sulfide or diallyl amine and reacting these brominated materials with an organic phosphite. The peroxygen or polychalkogen analogs of polyphospho compounds of this invention can be preparedby reacting, for example, sodium polysulfide with a halo unsaturated'hydrocarbon compound, hydrohalogenating the resulting polysulfide, and thereafter treating said halo polysulfide with an organic phosphite. The reaction proceeds as follows:

R -S. R t.I.HY Ya ntssaats aq Y VIII agzmsse (R is a hydrocarbylradi ea'l, Y is a halogen atom, and S5." represents mono,- (iitri-, and" otheifpoly-sulfides.)

Example I.'Bis[ (d ibutyl phosphono) methyl] ether mntmli emlao A mixture of 1 00 grams 0;8.7 mo1e) of sym-dichloromethylether and 5.00 grams (2.00 moles) of. redistilled trihutyl: phosphite were'hea-ted and the butyl chloride formedwas continuouslyren oved by means of a fracti onating column. 'Ehe reaction; started whenthe kettle temperature was about: 140 C. and was completed. when thetemperature reached about 202" C.- The residue was topped to 200 C. kettle temperature at lLmm. pressure to remove unreactedtributyl phosphite. The crude prod} uct was agitated with IM KQI-L at. 5.0.? C., washed with water, dried and distilled in a fallingrfilm; molecular still at 155 C. under 10- mm. pressure. Thisproduct, bis[(dibutyl phosph0no)methyl']ether hadthe. following properties;

- 5 6310.01 Fmlpd Theory Percent C 50.8 50. 2 PereeneH. I 9.5 9.3 B 14.1; 14.1 0 0 Q 1' U 0 0 B. P; at 1 mm .iscs-l M 2 V. I. (D andD)... Bourloin't.-.. c u. ..-c. F

Example 1r.- Bist-2,2' -bm z b'enzenephosphinibb)'ethyl] ether T [c.mo P lotus) 0520112110 Inte a flask containing 305- grams (1.2 moles) of dibntyl; benzenephosphonite heated at 165 C. was slowly added 1 16- grams (0:.5' mole). of 2 ,2'-dibromodiethyl ether. 'Fhe butyl-bromide, formed was; removed and the reaction mixture was. stabilized-by distilling off materials boiling bel ow. 100 C. under 1 to 2.mm Hg pressure and then distilled-in a molecular still. The purified bis[-2,2'(,buty1 benzenephosphinico)ethyl] ether had the following properties:

Exan1pl eI IKBis[ (di'b'utyli phasplioriolformoxyethyll ether About 120 grams (0.5 18mole of dichlo'rofonnateofi ethylene glycol obtained by the-interaction of ethylene. glycol and phosgen'e; was reacted with 325 grains (1.30

thereafter the reaction product was topped by distilling off materials boiling below 160 C. at 1- mme Hg-pressure. The? residue had a refractiveindex of n -11.45508 and had the following propertiesf Example IV.-'-Bisf (diisopfopyl phosphono ethyl] ether This product was produced by heating. for about 20 hours at C. a solution composed of about 500 grams of triisopropyl phosphite and about 100 grams of syrn dichloroethyl ether. The tetraester was recoverable by fractional distillation;

Example V.Bis[2-(Qdi-ri-liuzyl phzisphonayethylletlter Bis 2-(di-n-b'utyl phosphono)'ethyl'-Iethe'r was prepared by heating 3 moles of tributyl phosphite' to C.-at 40mm. pressure and slowly addingther'eto about 1' 11301 of bis(2'-bromoethyl)efhe'r The reaction mixture' was heated until no further butyl bromide was liberated and thereafter stabilized by heating to 156" C. at 5.0 pressure. The crude product was purified by heating under reflux with 1.2 N sodium hydroxide; the aqueous phase was removed and the product wate'f-washedand thereafter dried by heating at 150 C. and 5" mm. pressure.

The purified b'i'sEZ-(di-n butYL phosphonojetliyllether had the following properties:

Acid Neut. No. 0:09 risurpein t. 1F. -6 5 Yisc.,. 1'00'-F. (cs.)' 13".3'1 Viscosity fi 113 Acid Neut. No Y I 0.04 Four. point. F Visc., 100 F. (cs.) .-'-.'.l ViScQSity' inrlmfl 140 Example YrTl-Bis t'zdin'on r p'h'dsjphofib'j ethyll efh'er This product was prepared by reacting tri(nonyl) phosphite with bis(2-bromoethyl)ether at -200 C. and

17 mm. pressure. The product had the following properties:

Acid Neut. No 0.10 Pour point, F 30 Vise, 100 F. (cs.) 64.82 Viscosity in 117 Other examples of polyphospho ether compounds of this. invention for use in the practice of the invention are:

' B'isE (dieycloheityl phosphono) ethylJether Bis litdii'sopro'pyl phosphono) methyl] ether Bis (diisopropyl phosphono ethyl] ether 1 Bis I] ('dibfenzyl phosphono) methyl] thio ether BisE- (dibutyl phosphono methyl] ether B is'lllfdicresy l' phosphono) methyl] ether Bis lf tdio'c'tyl phosphono ethyl] ether Bis (dihexyl phosphono ethyl] ether 75 Bis[ (.butyl benzenephosphino)methyl] ether below 2'50 6. and then rapidly heated Bis (butyl chlorobenzenephosphino) methyl] ether Bis butyl trichloromethanephosphino methyl] ether Bis E dibutyl phosphono) formyl] oxide Bis (dibutyl l-phosphono phthaloyl] oxide Bis E dibutyl 1-phosphono)succinyl] oxide Bis[ dioctyl 2-phosphono -2-aminoethyll ether Bis dibutyl phosphono ethoxyethyl] ether Bis[ dibutyl phosphono ethoxy] ethane Bis[ diisopropyl 2-phosphono -2-methylolethyl] ether Bis dibenzyl 2-phosphono -2-methylolethyl] ether Bis[ (benzyl butyl phosphono)methyl]ether Bis E (phenyl butyl phosphono) methyl] ether Bis (dibutyl phosphono propyl] amine Bis (dihexyl 2-phosphono -2-chloroethyl] ether Bis [2- di sec. butyl phosphono ethyl] ether Bis dibutyl phosphono n-propyl] dithio ether Vehicles to which the phosphorus-containing substances of this invention may be added, for purposes of improving the lubricating qualities of said vehicles or for purposes of producing corrosion-preventing compositions and the like, may be divided into several groups.

The vehicles should preferably be substantially neutral, although they may be weakly acidic or weakly basic, preferably having dissociation contants not above about Both polar and non-polar vehicles may be employed. Among the former are water, monohydric alcohols, such as propyl, isopropyl, butyl, amyl, hexyl, cyclohexyl, heptyl, methylcyclohexyl, octyl, decyl, lauryl, myristyl, cetyl, stearyl, oleyl, allyl, benzyl, etc., alcohols,

polyhydric alcohols, such as ethylene glycol, propylene glycol, butylene glycol, cetene glycol, glycerol, methyl glycerol, 2-methylpentane-2,4-diol, trimethylene glycol, tetramethylene glycol, etc.; phenols and various alkyl phenols and thiophenols; ketones, such as acetone, methyl ethyl ketone, diethyl ketone, methyl propyl ketone, methyl butyl ketone, dipropyl ketone, cyclohexa'none, and higher ketones; keto alcohols; ethers such as diethyl ether, diisopropyl ether, ,B,B'-dichlorodiethyl ether, diphenyl oxide, chlorinated diphenyl oxide, diethylene glycol, triethylene glycol, monoand di-butyl ethers of ethylene glycol and diethylene glycol, and the like; neutral esters of carboxylic and other acids such as ethyl, propyl, butyl, amyl, octyl, stearyl, oleyl, phenyl, cresyl, and higher hydr'ocarbyl acetates, propionates, butyrates, lactates, laurates, myristates, palmitates, stearates, oleates, ricinoleates, phthalates, salicylates, carbonates, and phosphates; natural waxes such as carnauba wax, candelilla wax, Japan wax, jojoba oil, sperm oil; fats such as tallow, lard oil, olive oil, cottonseed oil, Perilla oil, linseed oil, tung'oil, soya bean oil, flaxseed oil, castor oil, etc.; as Well as fractions and derivatives thereof.

Vehicles of little or no polarity comprise hydrocarbons such as liquid butanes, pentanes, hexanes, heptanes, octanes, octenes, benzene, toluene, xylene, cumene, indene,

" and copolymers and the like.

hydrindene, alkyl naphth'alenes, and mixtures thereof as well as well known mixtures such as gasoline, kerosene, fuel oil, turbine oil, motor oil, mineral spirits, aromatic solvents, lubricating oils (which may be soap-thickened to form greases), petrolatum, paraflin Waxes, albino asphalts, etc. Generally, when petroleum oils are used it is preferable that they be purified, as by solvent treatment, so as to remove foreign matter.

Also, synthetic oils may be used as the vehicles such as polymerized olefins, copolymers of alkylene glycols and alkylene oxides; organic esters, e. g., di-Z-ethylhexyl sebacate, allyl laurate, and polymers thereof; dioctyl phthalate, trioctyl phosphate, polymeric tetrahydrofuran, polyalkyl silicon polymers, alkyl methacrylate polymers Mixtures of synthetic and natural lubricants and oils can be used. In addition, resinous materials such as petroleum resins, natural'resins such as rosin, resins formed by polymerization of drying fatty oils, phenol-formaldehyde resins, and glyptal-type resins formed by esterification of polyhydric alcohols with polycarboxylic acids can be used.

Still another class of vehicles to which condensation products of this invention can be added are water-in-oil and oil-in-Water emulsions suitable for various uses such as lubricating, cooling, rust inhibiting, and the like.

If the phosphorus compounds of this invention are not sufiiciently soluble in some of the mediums indicated above, solubilizers can be used.

The amount of additive of this invention which can be used depends upon the vehicle to which it is added and the intended purpose to which the composition is to be subjected. Generally, the'additive can be used in amounts varying from 0.01% to 20% and higher, preferably between 0.1% and 5%. Various .ones of the. phosphorus compounds of the invention are useful as lubricants per se,

-or where they constitute a major proportion of the lubricating medium. I I

Organic phospho compounds ofthis invention in addition to being good lubricant-improving agents can be used for improving greases, fuel compositions, hydraulic fluids, insecticidal compositions, coating compositions, rubber compositions, resinous compositions and the like.

The utility of the described phosphono compounds for lubrication is demonstrated by an evaluation of composi tions thereof by the Dornte Oxidation Stability Test as described in the National Petroleum News, September 17, 1941, pages R-294296 and in the High-Temperature Oxidation Apparatus of H. Diamond et al. which is fully described in the general papers presented before the Division of Petroleum Chemistry at the meeting of the American Chemical Society (September l8-23, 1949, Atlantic City, New Jersey) on pages 31-45 of the Preprints. Representative results are given in Table I.

TABLE I IBase: Mineral lubricating 01].]

Dornte Oxidation Test High Temperature Oxidation (150 0.) 1,500 00., Time Test (260 C.) 250 cc., Time (hours) (minutes) -Addmve Catalyst Cone. Catalyst Iglories;

ercen Copper ggg Percent None Copper gg Nona 23 4. 6 31 5. 1 6. 6 Example I:

Bislttldihutyl phosphono)-methyl] 1 37 16 1. 25 46 34 42 et er. Example III:

Bis[(dibutyl phosphono)-formoxy- 2.1 51 59 2.1 36 23 35 ethyl] ether. Dimethyl tetradecanephosphonate.. 1.2 7 4.2 1.2 42. 5 4.2 5.7 Dibutyl octanephosphonate 1. 3.9 3.9 1.2 30.4 3.6 '19.! Lauryl benzyl sulfide 1 24. 3 6. 2 1 40 12 5. 0 Dibenzyl sulfide.. 1 26.3 5.8 1 24 14 16 (The base mineral oil was a refined mineral lubricating oil.)

Representative compositions of this invention were evaluated neat and compared with other types of phosphorus compounds, as noted by Examples 6,. 7 and 8, by subjectingthem to. a modificationof the corrosion-oxidation resistance test in the presence of various metals as described in Federal Specification VVL-79ld', Test The results were as follows:

[Corrosion test: Wt; loss (mg./cm.

v Cw i Mg Fe Gd; Al

1'. Tetrebutyl bistphosphonoethyl} 1 r ethr J 0 as; 0.04 2., Bis[-2,2(butyl benzene-phosphinico)ethyl}ether 0. 04 0. 16 0 3', Bisfldibutylphosphono) -butyl]- Bethdfi.-..} .fi- -iz.---' 0 0. 0 4 13 on 05 one -e e e uigrflfnfilnflfir 0.04 1!);04 0 fiafiisliz' uty p-c oro'enzen hosph' co)-ethyllether. i -22 0 0.08 1 0.04 6;, Diallxllheuzenephosphonite 0.24 lit-.0 0.12 7. Dibutyl 2-ethylhexanephosphonate 0 7.56 0.08 8. Butyl n-octanephosphinate Very corrosive and unstable.

A hydraulic fluid consisting of the following materials was subjected to the corrosion test as described above and the results are tabulated below:

Compositions of this invention can be combined with other additives such as blooming agents, pour-point de- 'pressors, and/ or viscosity improvers,-anti-foaming agents, and the like. Among the specific additives for lubricating purposes which can be used are oil-soluble detergents which include oil-soluble salts of various bases with detergent-forming acids. Such bases include metal-containing as well as organic bases. Metallic bases include those of alkali metals, Ca, Mg, Cu, Sr, Ba, Zn, Cd, Al, Sn, Pb, Cr, Mn, Fe, Ni, G0, etc. Organic bases include various nitrogen bases as primary, secondary, tertiary amines and quaternary ammonium compounds, e. g., benzyl trimethyl ammonium hydroxide.

Examples of detergent-forming acids are the fatty acids of say, 10 to 30 carbon atoms, tall-oil acids, rosin acids, wool-fat acids, parafiin-wax acids (produced by oxidation of paraffin wax), chlorinated fatty acids, aromatic hydroxy fatty acids, paraflin-wax benzoic acids, various alkyl salicylic acids, phthalic acid monoesters, aromatic keto acids, aromatic ether acids, diphenols such as di- (alkylphenol) sulfides and disulfides, methylene bis-alkyl phenols; sulfonic acids such as may be produced by treatment of alkyl aryl hydrocarbons or high-boiling petroleum oils with sulfuric acids; sulfuric acid monoesters; phosphoric, arsonic and antimony acid mono-and di-esters, including the corresponding thiophosphoric and arsonic acids and the like.

Additional detergents are the alkaline earth phosphate diesters, including the thiophosphate di-esters; the alkaline earth diphenolates, specifically, the calcium and barium salts of diphenol monoand poly-sulfides.

Non-metallic detergents include compounds such as the phosphatides (lecithin and cephalin), certain fatty oils such as rapeseed oils, Voltolized fatty or mineral oils and the like.

An excellent detergent for the present purpose is the 10 calcium salt of oil-soluble petroleum sulfonic acids. This may be present advantageously in the amount ofabout 0.025% to- 0.2% sulfate ash. Also, alkaline metal salts of alkyl phenol-aldehyde condensation products are excellent detergents.

Antioxidants which are suitable for use in combination with the phosphono compounds comprise several types, for example, alkyl phenolssuch asv 2,4,6-trimethylphenol, pentamethylphenol, 2,4.-dimethyl--tertiary-butylphenol, 2,4-dimethyl-6-octylphenol, 2,6-ditertiary-butyl-4-methylphenol, 2,4,6-tritertiary-butylphenol, and thelik'e; aminophenols such as benzylaminophenols; aromatic amines, such as N,N'-dibutyl-p-phenylenediamine, diphenylamine, phenyl-beta-naphthylamine, phenyl-alpha naphthlyamine, and dinaphthylamine.

Corrosion inhibitors or anti-rusting compounds may also be present, such as dicarboxylic acids of 16 or more carbon atoms; alkali metal and alkaline earth salts of sulfonic acids and fatty acids, organic compounds containing an acidic radical in close proximity to a nitrile, nitro, or nitroso group (e. g, al'pha-cyanosteari o acid), glycidyl phenyl ether, wax disulfide, etc.

Additional ingredients may comprise oil-soluble urea or thiourea derivatives, e. g., urethanes, allophanates, carbazides, carbazones, etc., polyisobutylene polymers, unsaturated polymerized esters of fatty acids and monohydric alcohols and other high-molecular-weight oilsoluble compounds.

Depending upon the additional additive used and conditions under which it is used, the amount of additive used may vary from 0.01 to 2% or'higher. However, substantial improvement is obtained by using amounts ranging from 0.1 to 0.5% in combination with reaction prod ucts of this invention. a

We claim as our invention:

1. A composition of matter comprising a major amount of mineral oil and a minor amount, suflicient to inhibit oxidation, of bis[(dibutyl phosphono)methyl] ether.

2. A composition of matter comprising a major amount of mineral oil and a minor amount, sufficient to inhibit oxidation, of bis[(dibutyl phosphono)ethyl] ether.

3. A composition of matter comprising a major amount of mineral oil and a minor amount, suflicient to inhibit oxidation, of bis[(dibutyl phosphono)formoxyethyl]- ether.

4. A composition of matter comprising a major amount of mineral oil and a minor amount, suflicient to inhibit oxidation, of bis[-2,2'(butyl benzenephosphinico)ethyl]- ether.

5. A composition of matter comprising a major amount of mineral oil and a minor amount, suflicient to inhibit oxidation, of bis[(diisopropyl phosphono)ethyl]ether.

6. A composition of matter comprising a major amount of a mineral lubricating oil and a minor amount, suificient to inhibit oxidation, of bis[(dibutyl phosphono)methyl]- ether.

7. A composition of matter comprising a major amount of a mineral lubricating oil and a minor amount, sufiicient to inhibit oxidation, of bis[(dibutyl phosphono)- ethyl] ether.

8. A composition of matter comprising a major amount of a mineral lubricating oil and a minor amount, sufi'icient to inhibit oxidation, of bis[(dibutyl phosphono)- formoxyethyl] ether.

9. A composition of matter comprising a major amount of a mineral lubricating oil and a minor amount, sufiicient to inhibit oxidation, of bis[-2,2-(butyl benzenephosphinico)ethyl]ether.

10. A composition of matter comprising a major amount of mineral lubricating oil and a minor amount, sufficient to inhibit'oxidation of said oil, of a bis[(di- (C1- 1z)alkyl phosphono) C1 to C15 alkyllether.

11. A composition of matter comprising a major amount of mineral lubricating oil and a minor amount,

1 1 sufiicient to inhibit oxidation of said oil, of a bis[(C1 to C12 alkyl benzene phosphinico) C1 to C15 alkyllether.

12. A composition of matter comprising a major amount ofa mineral lubricating oil and a minor amount sufficient to inhibit oxidation of said hydrocarbon of a compound having the general formula (RO (il -n-o-qz-i 0 wherein each R is a saturated hydrocarbon radical of from 1 to 15 carbon atoms and R is a hydrocarbyl radical of from 1 to 12 carbon atoms.

13. A composition of matter comprising a major amount of a mineral lubricating oil and a minor amount sufficient to inhibit oxidation of said hydrocarbon of a compound having the general formula:

wherein R is a divalent organic radical selected from the References Cited in the file of this patent UNITED STATES PATENTS 2,174,019 Sullivan Sept. 26, 1939 2,373,670 Engelke Apr. 17, 1945 2,396,839 Evens et a1 Mar. 19, 1946 2,411,671 Smith et a1 Nov. 26, 1946 2,443,264 Mikeska June 15, 1948 2,486,658 Kosolapofi Nov. 1, 1949 2,502,400 Harris Mar. 28, 1950 2,629,731 Harman Feb. 24, 1953 2,632,756 Harman et al Mar. 24, 1953 2,634,288 .Boyer et a1. Apr. 7, 1953 2,642,461

Morris et a1. June 16, 1953 

13. A COMPOSITION OF MATTER COMPRISING A MAJOR AMOUNT OF A MINERAL LUBRICATING OIL AND A MINOR AMOUNT SUFFICIENT TO INHIBIT OXIDATION OF SAID HYDROCARBON OF A COMPOUND HAVING THE GENERAL FORMULA: 